Machine for molding brick shapes



c. L. NORTON. I MACHINE FOR MOLDING BRICK SHAPES.

APPLICATION FILED MA! 24, I921.

Patented Aug. 22, 1922.

2 SHEETS-SHEET I.

'0. L. NORTON.

, MACHINE FOR MOLDING BRICK SHAPES.

, APPLICATION man MAY 24' 1921.

1,426,761. PatentedAug. 22', 1922.

2 SHEETS-SHEET 2.

53 iz fz @Xw Wfya a CHARLES L. NORTON,

MACHINERY MANUFACTURING COMPANY,"0F

CORPORATION OF FENNSYLVANIA.

' i '5 an tr interns PITTSBURGH, PENNSYLVANIA, A

MACHINE FOR MOLDING BRICK SHAPES.

Application filed May 24,

To all whom- 'Zlli' may concern.

Be it known that I, UriAnLns LADD NoirroN, a citizen of the UnitedStates of America, and resident of Boston, in the. county of Suffolk andState of Massachusetts, have invented new and useful Improvements inMachines for Molding Brick Shapes, of which the following is aspecification.

In Letters Patent of the United States, numbered 1,332,676 and1,332,677, granted to me under date of March 2, 1920, there aredescribed and claimed a method and. machine for making molded bodies ofgranular or comminuted material the said method and machine beingparticularly addressed to the problem of automatically moldingaccurately formed and substantially homogeneous bodies,lsuchasbrickshapes, composed of hard, irregularly siaped, non-plasticgranules, such as the crushed ganister employed in the manufacture ofrefractory silica-brick.

While, pointed out in the said patents, crushed and granular ganisterfurnishes a conspicuous; example of the class of materials which respondto the described method but are ill adapted to other methods of moldingshapes such as bricks; similar characteristics, different doubtless indegree from, but like in kind to,'those which are possessed by crushedganister, render the said method. and the improvements thereon hereindescribed, advantageously applicable to a variety of materials, Forinstance, in the manufacture of clay lire-brick, the material oftenemployed is hard, stonelike clay, which like ganister rock has to beprepared by granulation. vThe granules of such clay, while not so hardas ganister granules, are evertheless far from plastic in their consiution, and resist molding pressure to a degree so pronounced that theedges and corners of clay fire brick shapes are notoriously imperfect,and the shapes themselves defective as regards homogeneity and uniformdensity. And, though the nioistening of such granulated hard clay, orthe mixture therewith of a pasty, less refractory clay, in proportionssuiliciently small to avoid undue deterioration oftheheatresistingproperty ofthe brick, pro- Specification of Letters Patent.Patented All, 22, 1922.

1921. Serial no. 472,245.

duces a coating of plastic and lubricant material on the hard granules,the granules themselves manifest their non-plastic and resistantcharacter by the aforesaid imperfections in product, when, as hasheretofore been the practice, this granular clay material has beenmolded by extrusion through dies. My method has proved effective to moldnot only silica brick, but also fire-claybrick, the material in bothcases possessing similar physical characteristics.

Before making application for the aforesaid patents, fi designed andcaused to be built andoperated, a machine (from which the'illustrativedrawings of the patents were made) inwhich the brick-molds were adaptedto formthe standard nine-inch silica brick forms, in groups of sixformsat a single charge. Since then, other machines have been built fromthe pattern furnished by the first one, which have successfullydemonstrated on a commercial scale the manufacture of brick by themethod described and claimed in the said patents, these machines beingalso designed and proportioned to make the standard nine inch silicabrick.

As set forth in the said patents, the physical condition characteristicof the method by which these bricks have been made, is the projection asby dropping, into a mold, of a dense swarm of individually non-plasticgranules, each slightly separated from its fellows, so that each hasavailable to it, for mobility in any direction a clear, thoughrestricted. space. At the instant before the swarnr of granules isconsolidated by the accumulated impacts of the individual granules uponthe surface of the mold, and against each other, the swarm presents asit were a vastly enlarged model of a drop of liquid, ,each granulerepresenting a mobile molecule; and-the consolidation or compacting ofthe swarm into the molded shape is, likewise, a model of or analogy to,the solidificatio or freezing, of a dropof liquid. In this sense, theswarm of individually solid granules is momentarily fluid, the granulesretaining mobility and continuing motion with relation to one anotherand during this interval the transition of each granule from itsoriginal straight path of movement through a series of rebounds andoscillating movements, progressively decreasing in length, to its finalposition of rest, takes place.

In order to produce efl'ectively the condit'ions'requisite to completelyfill the mold, thegranulescomposing each charge should be allowed tofall freely and without re- "ta'rdation, disturbance, or deflection, sothat each granule shall descend straight tothe place in the mold "whereits fall is arrested and its downward motion converted into a series ofvibratory rebounds by impact against the surface which first arrests it,

and then against other granules. For these reasons it is prescribed inthe said patents that the chute or tube through which the charge fallsfrom the hopperwhere it was accumulated to the mold which is to reeeiveit, shall be, particularly at its lower end, larger in horizontalcross-section than the i'nt-erio r'of the mold; this to avoidretardation or deflection of granules situated at the outside of thedescending swarm, by contact with the sides of the chute during descent.

\Vhile machines designed and made in substantial accordance with thespecifications and drawings ofthe said patents. orwhich amounts to thesame thing--duplicate s of the machine from which the said drawings wereprepared, have proved effective to perform the process and to producethe above described physical condition of the charge of granules, in themanufacture of the relatively simple standard nine inch silica brick,the molds for which are only as deep as the least lineal dimension ofthe brick-about two and one-quarter i'nches;

it has been discovered, first: that the regularity and continuity ofproduction of such standard brick is improved, and, second: theformation of large and irregular special silica brick shapes broughtwithin the'scope of my patented method, by im-- iirovements in methodand mechanism which form the subject of this specification and itscompanion filed contemporaneously, the object of which is to attain theclosest possible approximation to the ideal condition of a dense swarmof non-plastic granules, each surrounded by a clear though limited freespace in air, and each falling freely'and without diversion from itsgravitative path. and with no retardation except that produced byair-resistance, until it reaches that point or region in the mold whereits fall is arrested by impact either against the bottom of the mold oragainst the already compacted body formed by granules which arrivedearlier and are in process of finding their respective final lodgmentsin the accumulating mass of compacted material.

Moreover, in developing these improvements with perfected manipulationof gran- -ular and non-plastic materials as the immediate objective, Ihave discovered that the improvements, particularly in their preferredembodiments and exemplifications, are also adapted to the {production ofmolded shapes composed ofvplastic or semifluid material, which while sowell suited to manipulation by extrusion methods that such, operationswill doubtless always be resorted to when shapes of uniform crosssection are to be manufactured, are nevertheless occasionally moldedinto shapes which are incapable of being extruded. In the latter case,molded shapes of all degrees as asymmetry and irregularity may bemanufactured by the employment of the herein described improved methodsand apparatus formolding by projection and impact, as by droppinga'cha'rge of material into a mold.

Thus, thepresent improvements are applicable to the manufacture ofsimple shapes, of granular and non-plastic material, and tend towardgreater regularity of operation and superior quality of product, ascompared with the method and apparatus described in my said patents;they are applicable also to the manufacture of more complex,difficultand larger brick shapes than were practically within theoperative scope of my method and apparatus described in the saidpatents; though it is to be borne in mind that the fundamental principleexplained in those patents persists in these "improvements so long asthe material operated on is of the non-plastic granular character.

But, in certain aspects herein to be alluded to, the presentimprovements are also adapted to the formation of complex shapes, out ofplastic material, such as soft clay, and; of course, are also adapted tothe formation of si'mple'shapes 'of plastic material, though. it isbelieved that the extrusion method will be regarded "as more practicalbecause more economical of time and power, for the pro- ,duction ofsimple shapes, of uniform cross section In the mechanism, theseimprovements are embodied in and expressed by the design andconstruction of the hopper in which the mold charge is accumulated inpreparation for dropping to themold, in the mode of operation ofthehopper in relation to the accumulated charge,and i'n'the relationshipof the hopper to the mold.

In its aspect as a method, these improvements are concerned with themanner in which an accumulated charge is shaped, as in a hopper, withreference to the shape of the mold which is to receive the charge, withthe manner in which-the accumulated charge is released in order to fallto the mold, and with the manner in which the charge enters and fillsthe mold.

In the drawings hereto annexed, which illustrate these improvements,

Figure 1 represents a hopper and mold, the hopper provided with meansfor jarring its vertical sides, but otherwise constructed as shown in mypatents above referred to;

Figure 2, a top plan view of the hopper ofFig. 1;

Figure 3, a mold, and hopper 1n which a side and half the bottom swingas one piece;

Figure 41, a top plan view of the hopper of Fi 5; I

Figure 5, a mold, and hopper formed by the junction between stationaryend plates of two downwardly inclined swinging gates;

Figure 6-, a top plan view of the hopper of Fig. 7;

Figure 7, a mold, and hopper formed by two inclined swinging plateswhich comprise both ends and sides of the hopper;

Figure 8, a top plan view of the hopper of Fig. 9;

Figure 9, a perspective view of the hopper of Fig. 9; I

Figure 9*, an end view or the hopper shown in Fig. 9 with details added;

Figure 9 a side view of the same; Figures 10 and 11, perspective viewsof special brick shapes.

The drawings are, with the exception of Figs. 9, 9, 9 10 and 11,diagrammatic; the mechanism for opening and closing the hopper may be ofany specific character, such as, for instance, that shown in Figs. 4 and12 of Patent No. 1,332,676. Hopper-opening devices, adapted to quickaction, are shown in Figs. 9 and 9 and will be described hereinbelo'w.

The hopper shown in Patent 1,832,676 consisted of stationary verticallydisposed ends and sides, and a pair of swinging bottom gates, wh ch,meeting at a median line formed the bottom of the hopper when closedtogether. lVhen an accumulated charge of granular brick material in sucha' hopper is released, even though the separation of the bottom gates beabrupt, so that the granular material in the middle, first deprived ofvertical support, is not allowed time enough to fall appreciably inadvance of the material at the two sides of the bottom of theaccumulated charge, the material which was laterally supported by thesides and ends of the hopper, which adheres to the hopper to someextent, is appreciably delayed in its initial downward movement, andcommunicates this delay, by

retardation, to material which lay near though not in contact with thesides and ends of the hopper. There is produced, therefore, a shell ordelayed granules around and above the main swarm as the material fallsto the mold.

The several figures of drawing, hereto anneXed, from Fig. 1 to Fig. 9inclusive, illustrate various modes and mechanisms by which theaccumulated charge of granular material in a hopper may be released, i.e., deprived to support both vertical and lateral, practicallyinstantaneously, so that the charge starts to fall all at once.

In Figs. 1 and 2 the sides S (and the ends also if desired) are providedwith means for jarring or vibrating the vertical charge supportingmembers of the hopper, these being, as illustrated, knobs or projectionsK, K, and a shallow-toothed or corrugated rack J, which, at and duringthe brief time required to open the bot-torn gates G (hung on arms A andpivoted at P) are moved over the knobsK, jarring them and the sides S ofthe hopper, so that the vibration of the sides S loosens the granularmaterial from adhesive contact with them at the instant the verticalsupport of the gates G is withdrawn. Thus both lateral and verticalsupport are withdrawn from the charge in the hopper at the same time. p

In Figs. 3 and 1, the side S and gate G are secured together, and swingon the pivot P, to which they are secured by the arms A. The separationof the sides and gates laterally, between the ends E, E, removes bothlateral and vertical support from the charge simultaneously.

In Figs. 5 and 6, the'sides S of the hopper are flat plates'which,pivoted at P, converge together, forming a wedge shaped hopper-spacebetween the ends E, which are fixed. When the sides S are abruptly swungoutward, to the dotted line position, both lateral and vertical supportare withdrawn simultaneously from the charge.

In the instances illustrated in Figs. 1, to 6 inclusive, the ends E or Eof the hopper are stationary and vertical, so that, at the ends therewill be produced the same kind of retardation of granules as wasobserved with the hopper described in Patent No. 1,332,676, unless theends E or E be provided with means for jarring or vibrating them, suchas the knobs K and rack J, shown in Fig. 1. When, however, the hoppercharge, and the mold likewise, is narrow from end to end, the relativelysmall surface of the end pieces of the hopper will produce acorrespondingly small retardati on of marginal granules.

But, by preference and especially when large brick shapes of specialcontour, or relatively great depth, are to be made, all lateral andvertical support should be simulaway from the accumulated charge.

the hopper to open instantaneously.

taneously removed from the, accumulated charge in the hopper. This maybe accomplished by mounting the end pieces so that they, like, thesides, more outward and For instance, in Figs. 7,8 and 9, the hopper isshown as composed of two similar pieces, each, of which comprises a sideplate S and laterally inclined end pieces E joined to the side plate,the whole pivoted at P. When the sides and ends of a hopper thusconstructed. are abruptly swung apart, the entire accumulated charge isat one instant deprived of all support, and is momentarily suspended inthe air, an aggregate of granules in the mass-shape conferred upon it.by the hopper in which the charge was deposited.

A manner in which the sidesand ends oi a hopper can be abruptly openedis illus- -which. is attached a spring M, the other end of which isanchored to a portion of the frame of the building or other stationaryobject, as indicated at N. When the two members of the hopper are closedtogether, the springs M. are under tension. This tension is resisted andthe hopper kept closed, by means of the fixed tongue L2,, -fastened toone of the hopper members, and the pivoted latch R, pivotally mounted onthe other hopper member, in such relation to the tongue Q, that thelatch may engage the tongue and hold the hopper members closed. When thehopper is ready to discharge its contents, the latch R is abruptlydisengaged, as by a. hammer-blow against the boss R, and the springs M,Mcause l Vl'ien thehopper is to be filled again, the'two halves can bebrought together by hand, and latched in closed relation.

In efi'ect, and with various approximations to. the ideal condition, allthe devices above' described accomplish this purpose, of depriving theaccumulated charge substantially'of all. support at the same in stance,and leaving the mass of granules suspended in air for an {instant in theshape conferred upon it by the hopper. When this initial condition isobtained, it

follows that every granule in the charge will respond to gravitativepull at the same insta'nt andstart to fall directly downward. lVere thedescent in vacuo, the shape of the charge would be the same, and the"close aggregation be the same on arrival at the mold as on leaving'theposition of the hop-per.

But by reason of the discontinuity of solid material in the charge .in,and voided by, the hopper, the whole charge is interstitiallyfilled withair, which is continuous i the charge.

.cent from. the hopper positionto the mold, air resistance, and to someextent also diversity of bulk as between granule and granule, causes thecharge to loosen and open, producing. the dense swarm of airseparatedgranules which is the. desired physical condition of the charge on itsarrival at the mold.

Figures 5 and 7 of the drawings illustrate the. preferred, and the mostgenerally applicable and useful, exemplification of my improvements. Themold-charge, as'forme'd in the hopper,and as it descends and enters themold, is wedge-shaped, and falls with the thin end of the wedgedownward. In transverse section, the charge is like a lancehead.Entering the mold, a charge thus shaped strikes the bottom of the moldfirst, and makes initial impact of granuleslitt such by the constituentparts of the charge) at the central portion of the mold bottom. At thisinstant of first impact, the space between the thin part of thewedgeshaped charge and the sides of the mold is void-0i. brick-material;consequently the material. scattering by impacts and seeking paths ofleast resistance, flies in all directions from the central portion ofthe mold outward; the progressively thicker parts of the wedgeshapedcharge, entering themold, supply successive increments of the materialwhich, in the progressively decreasing lateral space available,similarly scatter outward (and prevent earlier arrivals of material'from returning toward the central part of the moldspace. The materialis thus projected with considerable force outwardly from the enteringcharge, and accumulates in the mold by building laterally and inwardly'lroai the sides. The molded charge, formed as it is by an operationwhich is continuous during thebrief interval required to fill the mold,presents no stratifioations or demarcations; but if successive layers ofmaterial, each of'the samevolume, were 'contrastingly colored in thehopper, the coloration of material when molded would present cross sections of a series of'conic sections, generally similar to the sectionsof surfaces produced by centrifugal action on a liquid in a rotatingvessel. The adaptation of this preferred exemplitication of myimprovements to the formation of brick shapes'o't granular non plasticmaterial has been already described. JVVhen, however, the-conditioncharacterized by a mold charge previously shaped to a form and volumesmaller in horizontal section than the mold, particularly when thecharge is tapered or wedge-shaped, is obtained, these improvementsfindfurther adaptation in thelield ofgenuinely plastic'materials, such asthe. finely comminuted, tempered During the few feet tion.

If the mold charge be of such plastic clay, shaped in a hopper so thatthe charge will fall into the mold without touching the sides thereofuntil its material splashes laterally by impact, especially if thecharge be made tapered orwedge-shaped so as to enter the mold edgefirst, irregular or complex shapes can be accurately molded, and shapesnot susceptible of being molded by extrusion may thus be automaticallyproduced. Projection, as by dropping,'of a mass of plastic material intoa mold, the mass beingequal to or greater than the mold in horizontalsection, so that the open top of the mold. is completely covered beforethe lower and lateral portions are filled, tends to imprison air in themold, which acts as a cushion to prevent the material from penetratingto all parts of the mold. For this reason previous methods of-moldingplastic material by dropping it from a height into a mold have beencharacterized by subdividing the plastic material into small bodies,such as pellets-each in itself plastic.and showering the pellets intothe mold. This method lacks the laterally directed explosive scatteringof the material such as is produced by the ar rest of a singleWedgeshaped mass. falling into the mold in the manner herein described.The initial and characteristic step in this improvement on my patentedmethod of forming brick-shapes of granular non-plastic material is thesubstantially instantaneous withdrawal of all support, both vertical andlateral, from a mold-charge accumulated in a'hopper, andformed therebyin a defined shape and volume, so that this defined shape and volume isnot sensibly altered by the removal of support.

If the proportions of the mold are such that'the mold charge in thehopper is narrow, and the hopper therefore has ends of relatively smallsuperficial extent, this ini tial characteristic step will beeffectively taken if the mold-charge be not sensibly altered in itsvertical transverse section, since marginal alteration in its verticallongitudinal sectionwillbe inconsiderable becauseof the'relativelyinconsiderable area of the ends of the mold-charge. For the manufactureof brick shapes which are narrow in horizontal section, therefore, allthat will be necessary at the hopper to accomplish the desiredresultwill be to provide sides and bottom adapted to abrupt and completewith drawal of support from the charge at all supported surfaces thereofexcept the ends.

But, if the brick-shape to be molded is substantially as broad as it islong, provision should be made for releasing vertical and lateralsupport from all supported surfaces of the mold-charge in the hopper, inthe manner described, so that the shape and volume of the mold-chargeshall be unaltered by the act of withdrawing support.

By means such as above described, the shape and bulk of the aggregate ofgranules is determined, both at the beginning of its descent, and at theterminus of descent, since the extent of separation of granules intransit through a given distance is susceptible of measurement.

What the initial shape and bulk'of the hopper charge shall be, in orderto secure practically perfect physical conditions in the charge at theinstant of arrival at the mold, is determined mainly with reference tothe interior horizontal cross sectional area of the mold. Let it havebeen determined, for instance, that a charge of granules opens out, orswells by special separation of its granular components, from thicknessw, in the hopper, to thickness 10 at the lower end of its descent (asindicated in Fig. 1).- If the internal horizontal width of the mold be10 then the hopper will be so proportioned that the thickness w of the"swarm of granules shall be slightly less than w A similar dimensionalrelation should be established as between the length of the mold and thelength of the hopper. To express the matter more exactly: the maximumhorizontal cross section of the mold-charge in the hopper should beuniformly and 'marginally smaller than the minimum horizontal interiorcross section of the mold by an area sufficient to allow for theexpansion of the charge by separation of granules during fall to themold, leaving preferably a slightexcessor clearance, so that the maximumhorizontal cross section of the expandedmoldcharge shall be a littleless than the mini- 'mum internal horizontal cross section of the mold.In other words, the desired condition" is obtained, if the horizontalprofile of the mold-charge in' the hopper, when superposed on thehorizontal profile of the interior of the mold (both as viewed fromabove) were to show the latter profileexceeding the for-- 'mer by aperipheral margin.

the mold-charge is transformed by the forces acting on it duringdescent, by the letter C. The line L, L, in Figs. 1, 3, and 7,indicates. diagrammatically the surplus material in the hopper whichlies above the line, that below the line representing the mold-charge,or the amount which will fill the mold level with the top thereof.

The horizontal cross section of the upper surplus material may be largerthan the interior horizontal section of the mold. The sectional ordimensional relationships above described, relate only to portions ofthe hopper charge which are destined to remain in the moldatterdeposition, and not to portions of the hopper charge which arethere in accumulated'as surplus to ensure compact filling of the toppart of the mold. There is therefore a practicaldistinction between thehopper-charge and'the mold-charge. In order to ensure a full charge inthe mold, the hopper charge contains morematerial than the filled mold,surplusdeposited above the mold bei-ng'removed and the top of themold-charge leveled-off, as described in my said patents. Themold-charge, when in the hopper constitutes only a part of thehopper-charge. That portion of the hoppercharge which, as themold-charge, is-destined to enter and remainin .the mold is the portionto be manipulatedin the manner herein described. Practically, the wholehopper charge will be deprived of support both vertically and laterallyto secure the results arrived at; so far as concerns the essentials,however, the condition of granules in the upper or surplus portion ofthe hopper-charge both at the beginning of and during descent is ofsecondary, or no special, consequence, so long as a surplus of materialis provided to furnish the final accumulation of compacted material overW the top, of the mold. By observing the rules s as portions of themolof proportion, construction, and operation above set forth, amold-charge of individually isolated and .mobile granules, in de-'scending into-,a mold, falls vertically in its entirety; each granulearrives at its region of arrest and impact in the gravitative straightline of: movement, andthus no granules distract or deflectothers duringdescent fiection. Reaction of granules upon each other is-deferred untilthe movement when such reaction of repeated impacts is desired,

in order to propel granules laterally to all Recesses, such as M (Fig. 7will be filled compactly by the improved method here described, andrelatively large and deep shapes, such as illustrated in Figs. 10 and11, can be made automatically by the chargedropping method. Heretofore,such large a and relatively. complex shapes have been producibleonly byaslow hand. method of gradual and progressive filling and tamping; andthe shapes produced have been variable in respect to'density andquality. Such shapes, produced instantaneously. by my improved method,are notonly manufactured with far greater rapidity than by hand, but -with accuracy anduniformity. In drying and firing, these automaticallymolded shapes suffer a ,loss by defects so small as to beinconsiderable.

' What I claim and desire to secure by Letters Patent is: 1. In amachine of the character designated, a mold, and a hopperabove the moldcomprising means adapted to depriveaa, mold-charge in the hopper. 0]":vertical and lateral support substantially simultaneously.

2. Ina machine of the character designated, a mold, and a hopperabovethemold -mold being larger than the maximum hori- .zontal, interiorcrosssectionof the mold-..

charge containing portion of the' -hopper.

8. In a machine-of the character designated, amold, and a'fhopper abovethemold comprising means adapted to sdGPIlVQ a mold-charge inthe. hopperof vertical and lateral supportsubstantially simultaneously,

the interior horizontal cross-section of the mold being larger thanthe'maxim um horizontaljinterior cross-jsection of the mold chargecontainingportion of the hopper by.

an amount atleast 'equaLto the expansion of the mold-chargecross-section during scent-of the charge to themold.

4. In a machine of the character designated, a mold, and a hopper abovethe mold.

having ,a downwardly pointing wedgeshaped interior, and means adaptedtodeprive a mold-charge in the hopper. of. vertical. and lateral support.

5. In a machine of the character desig. nated, a mold, and ahopper abovethe mold having a downwardly pointing -wedgeshaped interior, and meansadapted. to deprive av mold-charge lIlf.tl1. hopper of vertical andlateral support, the interior.

. horizontal cross-section of the mold being by reason of their-ownretardation or deof the material into substantially Wedge-- shaped form,and a means-for the discharge of the material, when .formed, from saidfirst..mentionedr means by gravity into a.

mold. positioned beneath the mechanism.

.7. A mold,.filling mechanism comprising a separable hopper adapted-forforming a predetermined amount. ofthe material into a substantiallywedge-shaped mass, and means for separating the parts of the hopper forthe discharge of the material, When formed, therefrom by gravity inzo amold positioned beneath the mechanism.

8. In a machine 0:"; the characrer designated, a mold, and a downwardlytapered hopper above the mold comprising means adapted to deprive amold-charge in the hopper of vertical and lateral support substantiallysimultaneously.

Signed by me at Boston, Massachusetts, this twenty-third day ofMay,1921.

' CHARLES L. NORTON.

